Disappearing Coolant 2003 MB140 Van
 

Hi guys

I have an MB140 and coolant seems to disappear overnight while parked.

Had hoses and pump checked to no avail, steam is coming from the exhaust and I also have condensation inside the oil filler cap with grey/milky oil forming at this point.

No water is leaking into the oil sump as dipstick is clean, also had pressure test on cooling system / head and all checked out fine.

Any ideas much appreciated.

Cheers

I'd say you have a blown head gasket.

does a pressure test also mean leakdown test? there may be a sliver of a fracture of the head gasket so the leakdown may be small. careful not to be impatient and be sure that the test is sound for verrrry slow leak as well.

milk in valve area is not always caused from water leak,it may also happen when the unit is not driven long enough to heat up the top side.(condensation)from lukewarm conditions. You most likely have a slight erosion around a water port in a head gasket,when the unit is in operation the head is swollen enough to keep it from being troublesome,But as it cools it shrinks and you get a leak into the exhaust.

I have got up this morning, I am in australia, and checked a couple things after going through the posts.

I didnt even start it up and found a sweet oil smell in my coolant bottle as well as residue on top of the water. Im also assuming its the head gasket and off to workshop tomorrow morning.


Thanks for help.